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Yes, I know this has already been done. But hey, why not.
Make an A* pathfinder in FB:
  1. Must use A* algorithm (Yes, it's neccisary Wink)
  2. Any Heuristic is allowed.
  3. Use different ground costs. Ground types include: Ground, Hills, Water, Walls, etc.
  4. Allow the ability to easily change the "board". I plan to use my own board to test it out.
  5. Have fun with it. I know it's A*, but try your best Wink
    [/list:o]

    I'll make my own A* routine. This is a challenge, not a contest. Good luck! Big Grin
Here is my code! I've posted it in the Projects Thread already but...
[syntax="qbasic"]
DefInt A-Z
'$Dynamic
Declare Sub ClearScreen()
Declare Sub DrawScreen()

Declare Sub FindPath()
Declare Sub AddToOpen(x As Integer, y As Integer)
Declare Sub AddToClosed(x As Integer, y As Integer)
Declare Sub AddToPath(x As Integer, y As Integer)
Declare Function IsOnOpen(x As Integer, y As Integer)
Declare Function IsOnClosed(x As Integer, y As Integer)

const Ground = 0
const Hill = 2
const Water = 1
const Wall = 4
const Start = 6
const Finish = 5

const False = 0
const True = Not False

const GroundCost = 10
const HillCost = 25
const WaterCost = 50

Type SquareType
fScore As Integer
gScore As Integer
hScore As Integer
mType As Integer
pX As Integer
pY As Integer
End Type

Type PointType
x As Integer
y As Integer
End Type
cls
Screen 18

Open "board.brd" For Input As #1
Input #1, sWidth, sHeight

Dim Shared Map(sWidth, sHeight) As SquareType
Dim Shared OpenList() As PointType
Dim Shared ClosedList() As PointType
Dim Shared Path() As PointType
Dim Shared mStart As PointType
Dim Shared mFinish As PointType
Dim Shared comp As PointType

For y = 1 To sHeight
For x = 1 To sWidth
Input #1, Map(x,y).mType
If Map(x,y).mType = Finish Then
mFinish.x = x
mFinish.y = y
ElseIf Map(x,y).mType = Start Then
mStart.x = x
mStart.y = y
End If
Next x
Next y
Close #1
Print "Finding Path"

FindPath

Print "Path Found"
sleep

ClearScreen
DrawScreen

Sleep
End

Sub FindPath()
'A* pathfinding Algorithm
Dim c As PointType 'Current Square
Dim onFinish As Integer

c.x = mStart.x 'Set the current square to
c.y = mStart.y 'the start square coord.

Do While onFinish = False 'Do this while we have not found the Finish square

AddToClosed c.x, c.y 'Add the current square to the Closed list
For y = -1 to 1
For x = -1 to 1
If Not Map((c.x + x),(c.y+y)).mType = Wall Then 'If it is not a Wall square
If (IsOnClosed((c.x + x),(c.y + y))) = False Then 'If it is not on the Closed List
If (IsOnOpen((c.x + x),(c.y + y))) = False Then 'It is not on the Open list, add it

'Calculate F, G, and H scores
'G First
If Map((c.x + x),(c.y + y)).mType = Ground Then
Map((c.x + x),(c.y + y)).gScore = Map((c.x),(c.y)).gScore + GroundCost
ElseIF Map((c.x + x),(c.y + y)).mType = Hill Then
Map((c.x + x),(c.y + y)).gScore = Map((c.x),(c.y)).gScore + HillCost
ElseIf Map((c.x + x),(c.y + y)).mType = Water Then
Map((c.x + x),(c.y + y)).gScore = Map((c.x),(c.y)).gScore + WaterCost
End If

'Now H score using Manhattan distance
hx = 10 * (ABS(((c.x + x)-(mFinish.x))))
hy = 10 * (ABS(((c.y + y)-(mFinish.y))))

Map((c.x + x),(c.y + y)).hScore = hx + hy

'Finally, the F score

Map((c.x + x),(c.y + y)).fScore = Map((c.x + x),(c.y + y)).gScore + Map((c.x + x),(c.y + y)).hScore

'Make the current square the parent of this square
Map((c.x + x),(c.y + y)).pX = c.x
Map((c.x + x),(c.y + y)).pY = c.y

'Then add this square to the Open List

AddToOpen (c.x + x), (c.y + y)

'If it's the finish square, we've found the path!
If (c.x + x) = mFinish.x And (c.y + y) = mFinish.y Then
onFinish = True
End If

Else 'Then it is on the Open List. Check to see if this is the better route

If Map((c.x + x),(c.y + y)).mType = Ground Then
tempG = Map((c.x),(c.y)).gScore + GroundCost
ElseIF Map((c.x + x),(c.y + y)).mType = Hill Then
tempG = Map((c.x),(c.y)).gScore + HillCost
ElseIf Map((c.x + x),(c.y + y)).mType = Water Then
tempG = Map((c.x),(c.y)).gScore + WaterCost
End If

If tempG < Map((c.x + x),(c.y + y)).gScore Then 'This is the better route
'Make the current square the parent of this square
Map((c.x + x),(c.y + y)).pX = c.x
Map((c.x + x),(c.y + y)).pY = c.y

'Recalculate G and F scores
'G
Map((c.x + x),(c.y + y)).gScore = tempG
'F
Map((c.x + x),(c.y + y)).fScore = Map((c.x + x),(c.y + y)).gScore + Map((c.x + x),(c.y + y)).hScore

End If

End If
End If
End If
Next x
Next y

'Go through the Open List to find the lowest F score
curScore = 20000
For i = 1 to uBound(OpenList)
If IsOnClosed((OpenList(i).x),(OpenList(i).y)) = False Then
If Map((OpenList(i).x),(OpenList(i).y)).fScore <= curScore Then
c.x = OpenList(i).x
c.y = OpenList(i).y
curScore = Map((OpenList(i).x),(OpenList(i).y)).fScore
End If
End If
Next i

Loop

'We've found the target square.
Dim onStart As Integer
c.x = mFinish.x
c.y = mFinish.y
i = 1
Do While onStart = False
AddToPath c.x,c.y

If c.x = mStart.x And c.y = mStart.y Then
onStart = True
End If

x = c.x
y = c.y

c.x = Map(x,y).pX 'Make the Current Square the parent square
c.y = Map(x,y).pY

i = i + 1 'Increment i
Loop

End Sub

Sub AddToOpen(x As Integer, y As Integer)
Dim TempOpen(uBound(OpenList)) As PointType

For i = 1 to uBound(OpenList)
TempOpen(i).x = OpenList(i).x
TempOpen(i).y = OpenList(i).y
Next i
size = uBound(OpenList)
Redim OpenList(size+1) As PointType

For i = 1 to uBound(TempOpen)
OpenList(i).x = TempOpen(i).x
OpenList(i).y = TempOpen(i).y
Next i

OpenList(uBound(OpenList)).x = x
OpenList(uBound(OpenList)).y = y
End Sub

Sub AddToClosed(x As Integer, y As Integer)
Dim TempClosed(uBound(ClosedList)) As PointType

For i = 1 to uBound(ClosedList)
TempClosed(i).x = ClosedList(i).x
TempClosed(i).y = ClosedList(i).y
Next i
size = uBound(ClosedList)
Redim ClosedList(size+1) As PointType

For i = 1 to uBound(TempClosed)
ClosedList(i).x = TempClosed(i).x
ClosedList(i).y = TempClosed(i).y
Next i

ClosedList(uBound(ClosedList)).x = x
ClosedList(uBound(ClosedList)).y = y
End Sub

Sub AddToPath(x As Integer, y As Integer)
Dim TempPath(uBound(Path)) As PointType

For i = 1 to uBound(Path)
TempPath(i).x = Path(i).x
TempPath(i).y = Path(i).y
Next i
size = uBound(Path)
Redim Path(size+1) As PointType

For i = 1 to uBound(TempPath)
Path(i).x = TempPath(i).x
Path(i).y = TempPath(i).y
Next i

Path(uBound(Path)).x = x
Path(uBound(Path)).y = y
End Sub

Function IsOnOpen(x As Integer, y As Integer)
For i = 1 to uBound(OpenList)
If OpenList(i).x = x And OpenList(i).y = y Then
'It's on the open list
IsOnOpen = True
Exit For
End If
Next i
End Function

Function IsOnClosed(x As Integer, y As Integer)
For i = 1 to uBound(ClosedList)
If ClosedList(i).x = x And ClosedList(i).y = y Then
'It's on the closed list
IsOnClosed = True
Exit For
End If
Next i
End Function

Sub ClearScreen()
Line (0,0)-(319,199), 0, BF
End Sub

Sub DrawScreen()
For y = 1 to uBound(Map, 2)
For x = 1 to uBound(Map,1)
Square = Map(x,y).mType
Select Case Square
Case Ground: Line(x * 10, y * 10)-(x * 10 + 10, y * 10 + 10), 2, BF
Case Hill: Line(x * 10, y * 10)-(x * 10 + 10, y * 10 + 10), 21, BF
Case Water: Line(x * 10, y * 10)-(x * 10 + 10, y * 10 + 10), 33, BF
Case Wall: Line(x * 10, y * 10)-(x * 10 + 10, y * 10 + 10), 8, BF
Case Start: Line(x * 10, y * 10)-(x * 10 + 10, y * 10 + 10), 15, BF
Case Finish: Line(x * 10, y * 10)-(x * 10 + 10, y * 10 + 10), 4, BF
End Select
Next x
Next y
Dim ox, oy As Integer
ox = mFinish.x
oy = mFinish.y

For i = 1 To uBound(Path)
x = Path(i).x
y = Path(i).y
Line (ox * 10 + 5,oy * 10 + 5)-(x * 10 + 5,y * 10 + 5), 14
ox = x
oy = y
Next i

Locate 20,1
For i = 1 To uBound(Path)
Print Path(i).x;
Print ",";
Print Path(i).y;
Next i
End Sub
[/syntax]

You'll need to make a "board.brd" file to use it. Here is a sample board.

Code:
20,15
0,0,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0
0,0,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0
0,0,0,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0
0,0,0,5,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0
0,0,0,0,2,2,2,2,2,2,1,1,2,2,2,0,0,0,0,0
0,0,0,2,2,2,2,2,2,2,2,2,2,2,2,2,0,0,0,0
0,0,0,2,2,2,2,2,2,2,2,2,2,2,2,2,2,0,0,0
0,0,0,0,2,2,2,2,2,1,1,2,2,2,0,0,0,0,0,0
0,0,0,0,0,0,2,2,2,2,1,1,0,0,0,0,0,0,0,0
0,0,0,0,0,0,0,2,2,0,1,1,0,0,0,0,0,0,0,0
0,0,0,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
0,0,0,0,0,0,0,0,0,0,1,1,0,0,0,0,0,6,0,0
0,0,0,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0
0,0,0,0,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0
Hmm... nobody wants to do this eh? Sad Oh well, it was worth a shot. At least two other people are making one.
mine was already under the projects forum too... fb only

[syntax="qbasic"]#include once "crt.bi"
#define WALL 4
#define FINISH 5
#define START 6

option explicit

type coord
x as ubyte
y as ubyte
end type
type node
x as ubyte
y as ubyte
g as integer
f as integer
p as node ptr
end type

declare function timesvisited( byval x as integer, byval y as integer ) as byte
declare function outofbounds( byval x as integer, byval y as integer ) as byte
declare function onclosedlist( byref what as coord ) as byte
declare function removefromopenlist( byval idx as integer ) as byte
declare function onopenlist( byref what as coord ) as byte

redim preserve shared openlist( 0 ) as node ptr, closedlist( 1 ) as coord, allnodes( 0 ) as node ptr
dim as integer rx, ry, cx, cy, ex, ey, i
dim as string yn

input "show path? [y/n]:", yn
yn = ucase$( left$( yn, 1 ) )

cls
dim shared as integer mx, my
read mx
read my
dim as ubyte room( mx * my )
for ry = 0 to my - 1
for rx = 0 to mx - 1
read room( rx + ry * mx )
select case room( rx + ry * mx )
case WALL
? "|";
case START
? "@";
cx = rx
cy = ry
closedlist( 0 ).x = rx
closedlist( 0 ).y = ry
case FINISH
? "*";
ex = rx
ey = ry
case else
? " ";
end select
next
?
next

if yn = "Y" then sleep

dim as node ptr tmpnode
tmpnode = callocate( len( node ) )
tmpnode->x = cx
tmpnode->y = cy
allnodes( ubound( allnodes ) ) = tmpnode
redim preserve shared allnodes( ubound( allnodes ) + 1 )
while cx <> ex or cy <> ey

dim as integer max = 100, aye, x, y

aye = 0

for x = -1 to 1
for y = -1 to 1 step 1 - ( x = 0 )

dim as coord working
working.x = cx + x
working.y = cy + y

if onclosedlist( working ) = 0 and onopenlist( working ) = 0 and _
room( cx + x + ( cy + y ) * mx ) <> WALL and _
room( cx + ( cy + y ) * mx ) <> WALL and _
room( cx + x + cy * mx ) <> WALL and _
outofbounds( cx + x, cy + y ) = 0 then

openlist( ubound( openlist ) ) = callocate( len( node ) )
dim as node ptr temp
temp = openlist( ubound( openlist ) ) '' use a temp var so we don't have to
'' keep using ubound()
temp->x = working.x
temp->y = working.y

temp->f = 10 * sqr( abs( x ) + abs( y ) ) + _ '' the g score
10 * sqr( ( cx + x - ex ) ^ 2 + ( cy + y - ey ) ^ 2 ) '' the h score
if temp->f > max then max = temp->f
temp->p = tmpnode

allnodes( ubound( allnodes ) ) = temp
redim preserve shared allnodes( ubound( allnodes ) + 1 )

redim preserve shared openlist( ubound( openlist ) + 1 )

end if

next
next

dim as integer lowest, lowestidx = 0
lowest = max + 1
for i = 0 to ubound( openlist ) - 1
if openlist( i )->f < lowest and openlist( i )->f <> -1 then
lowest = openlist( i )->f
lowestidx = i
end if
next

if yn = "Y" then locate cy + 1, cx + 1: ? " "

if lowest <> max + 1 then
cx = openlist( lowestidx )->x
cy = openlist( lowestidx )->y
end if

if yn = "Y" then locate cy + 1, cx + 1: ? "@"

closedlist( ubound( closedlist ) ).x = cx
closedlist( ubound( closedlist ) ).y = cy
redim preserve shared closedlist( ubound( closedlist ) + 1 )

tmpnode = openlist( lowestidx )
removefromopenlist( lowestidx )

if yn = "Y" then sleep

wend

'' as a function this would return tmpnode

while tmpnode <> 0
locate tmpnode->y + 1, tmpnode->x + 1
? "*"
tmpnode = tmpnode->p
wend

'' it will be necessary to clean up memory afterward, otherwise we'll end up with
'' a leak the size of the pacific ocean ;P

for i = 0 to ubound( allnodes )

deallocate allnodes( i )

next

sleep

end

data 12,10
data 4,4,4,4,4,4,4,4,4,4,4,4
data 4,0,0,0,0,0,0,0,0,0,0,4
data 4,0,0,0,0,0,0,0,0,0,0,4
data 4,0,0,0,4,4,4,0,0,0,0,4
data 4,0,0,0,0,0,0,4,0,0,0,4
data 4,0,0,0,0,6,0,4,0,5,0,4
data 4,0,0,0,0,0,0,4,0,0,0,4
data 4,0,0,0,4,4,4,0,0,0,0,4
data 4,0,0,0,0,0,0,0,0,0,0,4
data 4,4,4,4,4,4,4,4,4,4,4,4

function outofbounds( byval x as integer, byval y as integer ) as byte

return x < 0 or x > mx - 1 or y < 0 or y > my - 1

end function

function onclosedlist( byref what as coord ) as byte

dim as integer i
for i = 0 to ubound( closedlist ) - 1
if memcmp( @closedlist( i ), @what, len( coord ) ) = 0 then return -1
next
return 0

end function

function removefromopenlist( byval idx as integer ) as byte

if idx > ubound( openlist ) then return 0
dim as integer i
for i = idx to ubound( openlist ) - 1
openlist( i ) = openlist( i + 1 )
next
redim preserve openlist( ubound( openlist ) - 1 )

return -1

end function

function onopenlist( byref what as coord ) as byte

dim as integer i
for i = 0 to ubound( openlist ) - 1
if memcmp( openlist( i ), @what, len( coord ) ) = 0 then return -1
next
return 0

end function
[/syntax]
I don't see how coding it in fb is any different from coding it in qb...I've done a qb version does that count?
Quote:I don't see how coding it in fb is any different from coding it in qb..

FB has some more helpful advanced functions ect ect

soo a QB version should work ^^
Ok, I completely redid my code....Here it is...this one supports multivalue land and diagonals...Smile
Code:
'*******************************************************************************
'Uses my own version of the a* pathfinding algorithim to store                 *
'*******************************************************************************
Declare Function FindPath (argStartX As Integer, argStartY As Integer, argDestX As Integer, argDestY As Integer ) As Integer
'*******************************************************************************
'Node Handling Subs for pathfinding                                            *
'*******************************************************************************
Declare Sub SpawnNode ( argX As Integer, argY As Integer, argParent As Integer, argStepCost As Double, argRealCost As Double, argMultiplier As Double, argSteps As Integer )
Declare Sub HandleNodes()
'*******************************************************************************
'Node Handling Functions                                                       *
'*******************************************************************************
Declare Function UnusedNode () As Integer 'find an unused node
Declare Function NodeCollideCompare ( argX As Integer, argY As Integer, argCompareCost As Double ) As Integer 'see if a spot already has a node
Declare Function AllNodesClosed () As Integer 'see if we are done

Const True = -1
Const False = Not True

Const CUnused = 0
Const COpen = 1
Const CClosed = 2
'Tiletype constants
Const CWall = 0
Const CFloor = 1
'Generating Maximum Constants
Const MaxPaths = 500
Const MaxNodes = 1000
Const StraightCost = 1
Const DiagonalCost = SQR(2)

Type NodeType ' used by the algorithim to find a path
    X As Integer 'horizontal position
    Y As Integer 'vertical position
    Parent As Integer 'index # of parent node    
    Status As Byte 'unused, open, closed
    Steps As Integer 'how many steps, regardless of diagonal/straight
    StepCost As Double 'doesn't factor different type of enviro
    RealCost As Double 'does factor real enviro
End Type

Type PathType 'used to record the steps of a path
    Steps As Integer 'how many steps
    X( MaxPaths - 1 ) As Integer 'max of 500 steps
    Y( MaxPaths - 1 ) As Integer 'max of 500 steps
    InUse As Byte 'is this in use
End Type

Dim Shared Node( MaxNodes - 1 ) As NodeType
Dim Shared Path( 99 ) As PathType 'stores a max of 100, 500 step paths
Dim Shared MapMaxX, MapMaxY
Read MapMaxX, MapMaxY
Redim Shared Map( -1 to MapMaxX , -1 to MapMaxY ) As Integer
For TempY = 0 To MapMaxY - 1
    For TempX = 0 To MapMaxX - 1
        Read TempTile
        Map( TempY, TempX ) = TempTile
        Locate TempY + 1, TempX * 2 + 1: Print TempTile
    Next TempX
Next TempY

Dim Shared CurNode As Integer
Dim PathIn As Integer
Dim TempS As Integer
color 4
print path( pathin ).steps
color 15
PathIn = FindPath (0, 0, 9, 9)
For TempS = 0 to Path( PathIn ).Steps
    
    Locate Path( PathIn ).Y( TempS ) + 1, Path( PathIn ).X( TempS ) * 2 + 1
    color 4
    sleep
    print " P"'Map(Path( PathIn ).X( TempS ) , Path( PathIn ).Y( TempS ) )
next tempS    
sleep
'*******************************************************************************
'Following function stores a path and then returns the index it's stored at    *
'*******************************************************************************
Function FindPath (argStartX As Integer, argStartY As Integer, argDestX As Integer, argDestY As Integer ) As Integer
    Dim TempLowestVal As Double 'lowest cost path
    Dim TempLowestNum As Integer 'index of lowest cost path node
    Dim TempNode As Integer
    Dim TempPath As Integer
    Dim TempCount As Integer
        
    CurNode = 0
    Node( CurNode ).X = argStartX
    Node( CurNode ).Y = argStartY
    Node( CurNode ).Status = COpen
    Node( CurNode ).Steps = 0
    Node( CurNode ).StepCost = 0
    Node( CurNode ).RealCost = 0
    
    Do
        HandleNodes
    Loop Until AllNodesClosed
    
    TempLowestVal = 100000000 'some ridiculous number so that it gets overridden
    TempLowestNum = -1 'give a illegal number to determine whether or not there is a path
    
    For TempNode = 1 To MaxNodes - 1'we know that 0 cannot be it, unless start and dest are the same
        
        If Node( TempNode ).X = argDestX Then 'if in the right column...
            
            If Node( TempNode ).Y = argDestY Then '...and the right row
                If Node( TempNode ).RealCost < TempLowestVal Then 'if this path costs less
                    
                    TempLowestVal = Node( TempNode ).RealCost 'overwrite current lowest data
                    TempLowestNum = TempNode
                End if
            End If
        End If
    Next TempNode
    
    If TempLowestNum >= 0 Then
        For TempPath = 0 to MaxPaths - 1
            If Path( TempPath ).InUse = False Then
                TempNode = TempLowestNum
                Path( TempPath ).Steps = Node( TempNode ).Steps
                Path( TempPath ).InUse = True
                For TempCount = Node( TempNode ).Steps To 0 Step -1 'have to count down due to the properties of parents
                    Path( TempPath ).Y( TempCount ) = Node( TempNode ).X
                    Path( TempPath ).X( TempCount ) = Node( TempNode ).Y
                    TempNode = Node( TempNode ).Parent 'go back one step, until we reach origin
                Next TempCount
                Return TempPath 'return the index of where we stored the path
            End If
        Next TempPath
    End If        
    Return -1 'return an illegal index number, there is no path
End Function
'*******************************************************************************
'Node Spawning Sub. Give it the new x, y. parents #, parents step and real cost*
'and the multiplier that corresponds to the new nodes direction to the parent  *
'*******************************************************************************
Sub SpawnNode ( argX As Integer, argY As Integer, argParent As Integer, argStepCost As Double, argRealCost As Double, argMultiplier As Double, argSteps As Integer )
    If argX < 0 Or argX >= MapMaxX Then Exit Sub    
    If argY < 0 Or argY >= MapMaxY Then Exit Sub
    If Map( argX, argY ) = CWall Then Exit Sub
    
    Dim TempNode As Integer
    Dim TempRealCost As Double
    Dim wt as Double
    
    TempRealCost = argRealCost + Map( argX, argY ) * argMultiplier
    If NodeCollideCompare( argX, argY, TempRealCost ) = False Then
        TempNode = UnusedNode
        Node( TempNode ).X = argX
        Node( TempNode ).Y = argY
        Node( TempNode ).Parent = argParent
        Node( TempNode ).Status = COpen
        Node( TempNode ).StepCost = argStepCost + argMultiplier
        Node( TempNode ).RealCost = TempRealCost
        Node( TempNode ).Steps = argSteps + 1
    End If    
End Sub
'*******************************************************************************
'spawn children then close the node                                            *
'*******************************************************************************
Sub HandleNodes()
    Dim TempNode As Integer
    Dim TempX As Integer, TempY As Integer
    
    For TempNode = 0 to MaxNodes - 1
        If Node( TempNode ).Status = COpen  Then
            For TempX = -1 to 1
                For TempY = -1 to 1
                    If Map(TempX + Node( TempNode ).X , TempY+Node( TempNode ).Y ) <> CWall Then
                        If Abs( TempX ) + Abs( TempY ) = 1 Then 'if walking straight
                            SpawnNode Node( TempNode ).X + TempX, Node( TempNode ).Y + TempY, TempNode, Node( TempNode ).StepCost, Node( TempNode ).RealCost, StraightCost, Node( TempNode ).Steps
                        End If
                        If Abs( TempX ) + Abs( TempY ) = 2 Then 'if walking diagonal
                            SpawnNode Node( TempNode ).X + TempX, Node( TempNode ).Y + TempY, TempNode, Node( TempNode ).StepCost, Node( TempNode ).RealCost, DiagonalCost, Node( TempNode ).Steps
                        End If
                    End If
                Next TempY
            Next TempX
            Node( TempNode ).Status = CClosed
        End If
    Next TempNode
End Sub
'*******************************************************************************
'Node Handling Functions                                                       *
'*******************************************************************************
Function UnusedNode () As Integer 'find an unused node
    CurNode +=1
    Return CurNode
End Function
'*******************************************************************************
'Check to see if a spot already contains a node, and then if it is better,     *
'return true                                                                   *
'*******************************************************************************
Function NodeCollideCompare ( argX As Integer, argY As Integer, argCompareCost As Double ) As Integer
    Dim TempNode As Integer
    For TempNode = 0 To MaxNodes - 1
        If Node( TempNode ).X = argX Then
            If Node( TempNode ).Y = argY Then
                If Node( TempNode ).RealCost <= argCompareCost Then 'if the current node there costs less
                    Return True 'then tell it there is a better one
                End if              
            End If            
        End If
    Next TempNode
    Return False
End Function
'*******************************************************************************
'Check to see if all nodes are either closed or unused                         *
'*******************************************************************************
Function AllNodesClosed () As Integer 'see if we are done
    Dim TempNode As Integer
    For TempNode = 0 to MaxNodes - 1
        If Node( TempNode ).Status = COpen Then Return False
    Next TempNode
    Return True
End Function

Data 10,10
Data 1,1,1,1,1,1,1,1,1,1
Data 1,0,0,0,0,0,0,0,0,1
Data 1,0,1,1,1,1,1,1,1,1
Data 1,0,1,1,1,1,1,1,1,1
Data 0,0,1,0,0,0,0,0,0,0
Data 1,1,1,0,1,1,1,0,1,1
Data 1,1,1,0,1,0,1,0,1,1
Data 1,1,1,0,1,0,1,0,1,1
Data 1,1,1,1,1,0,1,1,1,1
Data 1,1,1,1,1,0,1,1,1,1
I edited my code....comments on the new code are welcome. Smile
What FBC version are you using? It renders errors in 0.13. . .
For example, SQR(2) is not a constant. You could use #define DiagonalCost = SQR(2) for that one.
I am using the latest version of FBC, which is 14. And I get no errors....

And the last time I checked...the square root of two never changes. Tongue